@book{dirac,
author={Paul Adrian Maurice Dirac},
title={Principles of Quantum Mechanics},
publisher={Oxford Science Publications},
edition={Fourth},
year={2007}
}
@article{citeulike4770781,
	author = {O. L. de Lange and R. E. Raab},
	title = {Ladder Operators for Orbital Angular Momentum},
	journal = {American Journal of Physics},
	keywords = {angular-momentum, ladder-operators, quant-ph},
	number = {4},
	pages = {372--375},
	posted-at = {2009-06-07 23:00:22},
	priority = {2},
	publisher = {AAPT},
	url = {http://dx.doi.org/10.1119/1.14625},
	volume = {54},
	year = {1986}
}
